Roller conveyer



March 25, 1941.

s. EGGLESTQN ROLLER CONVEYER Filed July 11, 1938 Q r ZJ Patented Mar. 25, 1941 UNITED STATES .artnr OFFICE ROLLER ooNvEYER `Application July l1, 1938, Serial No. 218,624

13 ClaimS.

It is an object of this invention to provide a roller conveyer with a novel arrangement of resilient and independently movable supports for the several rollers whereby movement of heavy loads having uneven riding surfaces is facilitated andthe rollers are protected against ldamage from overloads and impact.

Another object is to provide in a conveyer of this class unusually long, light springs for actuating the individual rollers and individually movable roller supports so arranged relative to the springs as to obtain indirect application of the load to the springs and substantial mechanical advantage due to lever action.

A further object is to provide a conveyer of this class adapted to permit easy deflection of the individual rollers to an unusual degree upon increase in the load beyond a predetermined magnitude or the rated capacity of the individual rollers. v

A still further object is to provide unusually compact, neat and eficient mechanism for independently and resiliently supporting the several rollers of a conveyer.

In the accompanying drawing, illustrating one embodiment of my invention:

Figure 1 is a side elevation of a roller conveyer section;

Fig. 2 is a plan View, on a larger scale, showing a shorter section with a portion of one roller and all of another removed to show parts otherwise concealed;

Fig. 3 is a side elevation, with a portion of one of the longitudinal frame members broken away, and

Fig. 4 is a vertical, cross section through the conveyer frame.

Referring to 'the drawing, my improved conveyer has a pair of spaced, parallel and longitudinally extending frame members, each formed with a horizontal leg 5 and a vertical leg 6, rigidly joined together at suitable intervals by cross members 1. These frame members are constructed from heavy angle bars and the ends of the members 1 are preferably secured to the legs 5 and 6 by welding. The vertical legs 6 of the rigid frame are perforated 'near their upper edges to receive shafts 8, extending parallel to each other, for pivotally supporting the several rollers on the frame. The ends of the shafts 8 project slightly from the outer faces of the legs 6 and are fastened against longitudinal movement by cotter keys 9.

Conveyer rollers I0 are severally provided with i` anti-friction bearings on axial shafts II and these shafts are severally supported at their ends on pairs of bars I2. Each pair of bars I2 is pivotally supported on one of the shafts 8 to oscillate adjacent to the inner faces of the legs E respectively. A roller ID is supported on the 5 upper ends of each pair of bars I2 and near their lower ends these bars are joined together by a rod I3 extending parallel to the axis of the roller. Coiled springs I4, preferably of the tension type, are severally arranged to extend obliquely from a shaft 8 beneath one roller to the rod I3 beneath an adjacent roller, a pair of these springs being provided to actuate each roller support comprising a rod 8, pair of bars I2 and a rod I3. One end of each spring is secured by coiling it around one of the shafts 8 and the t other end is fastened to a rod I3 and confined between a bar I2 and a large washer I5 held against movement away from the spring by a cotter key I6 inserted through a perforation in the rod I3. Pivotal movement of each bar I2 about its supporting shaft 8 in a clockwise direction from the normal, full-line position shown in Fig. 3 is prevented by a rigid stop I'I which projects from and is welded to the inner face of one 5 of the legs 6. f

In the normal position of rest, the several rollers I0 have their upper peripheries disposed substantially in a common plane but each is movable independently of the others to a depressed position, such as that indicated in dotted lines in Fig. 3, against the action of the springs I4 under loads in excess of a predetermined magnitilde, which is commonly referred to as the rated capacity of the rollers. The axis of each roller I is offset longitudinally of the conveyer from the pivotal axis or supporting shaft 8 so that only a small part of the total load on the roller is transmitted to the springs. The springs I4 are preferably so designed that they are completely retracted and without deflection when the supporting bars I2 are in engagement with the stops I'l. By this arrangement an important mechanical advantage is obtained and a relatively large deection or extension of the springs is effected by relatively slight downward deflections of the rollers. Relativelylight, long springs may be employed for conveyers having high load capacity and at the same time an unusually compact conveyer is afforded as a result of the oblique, interior arrangement of the springs relative to the compact frame. The use of long springs is desirable to give smooth operation and ease of movement of heavy load-s having uneven riding surfaces which cause deflection of the rollers successively.

Where the heavy objects or loads to be conveyed have large projections on the bottom or riding surfaces, such loads should be moved in the direction indicated by arrows in Figs. 1 and 3 to facilitate the deflection of the rollers.

In conveyers of this class it is desirable that there shall be no deflection of the rollers under loads below their rated capacity but upon increase of the load above that magnitude the springs ordinarily should permit depression of individual rollers up to about one-half inch. If large increase in the load is required to produce such deilection, movement of the load is seriously interfered with. Only slight increase in the load above rated capacity produces ample deilection of the rollers of my conveyer. Tests have shown, for example, that in the case of one embodiment of my conveyer having a rated capacity of one thousand pounds per roller and with the springs i4 and other roller supporting elements arranged as herein illustrated and described, a downward deflection of the roller equal to one-quarter of an inch was obtained upon increase of the load to 1020 pounds and a further deflection up to a total of one-half an inch was produced by an increase of the load to approximately 1060 pounds. This relatively large deflection of the roller for the stated proportional increase in the load above the rated capacity of the rollers is extremely desirable in promoting ease of movement of heavy, uneven loads and in aording protection of the rollers against damage from shock and impact in placing the loads on the conveyer.

It will be understood that the degree of mechanical advantage of the springs over the load and amplitude of the deection of the rollers for given increases in the load above the roller capacity may be varied by changing the eiiective lever arms of the bars l2 as determined by the positions of the pivotal shafts 8 relative to the shafts Il and springs I4 and dimensions of the supporting bars I2.

Having described my invention, what I claim as new and desire to protect by Letters Patent is:

1. In a roller conveyer, a frame, a roller support, means pivotally connecting said support to said frame and conning said support to oscillating movement about a substantially horizontal axis relative to the frame, a conveyer roller revolubly mounted on said support obliquely above and to one side of said axis and resilient means engaging said support below said axis for restraining pivotal movement of said support relative to the frame.

2. In a roller conveyer, spaced, parallel frame members, a plurality of pairs of bars pivotally supported on said frame members for oscillating movement about substantially horizontal axes relative to said frame members, a roller revolubly supported on each pair of said bars above and to one side of the pivotal axis thereof and resilient means severally connected to the bars below their pivotal axes for restraining oscillating movement of the bars and permitting the rollers to be depressed independently of each other under predetermined loads.

3. In a roller conveyer, spaced, parallel frame members, a plurality of pairs of bars, means ivotally supporting the several pairs of bars on said frame members and between the same, said means confining the bars to oscillating movement about substantially horizontal axes relative to said frame members and each of said bars projecting above and Vbelow its pivotal axis, a roller revolubly supported on each pair of said bars above and to one side of the pivotal axis thereof and springs severally engaging said bars below their pivotal axes to support the rollers and permit them to be depressed independently of each other under predetermined loads.

4. In a roller conveyer, spaced, parallel frame members, a roller support pivotally mounted on said frame members for oscillating movement about a substantially horizontal axis, a roller mounted on the upper portion of said support, means for limiting pivotal movement of said support in one direction and a coiled spring having one end engaging said support and the other end engaging one of said frame members to resiliently support said roller in elevated position, said spring extending from the lower portion of said support obliquely upwardly and longitudinally of said frame members between the same,

5. In a roller conveyer, spaced, parallel frame members, a roller support, means pivotally connecting said support to said frame members between the same and confining said support to oscillating movement about aisubstantially horizontal axis, said support projecting obliquely above said axis and beneath the same, a roller mounted on the upper portion of said support, a stop limiting oscillating pivotal movement of said support in one direction and a coiled tension spring having one end connected to the lower portion of said support and the other end connected to one of said frame members, said spring extending from the lower portion of said support obliquely upwardly and longitudinally between said frame members to resiliently support said roller.

6. In a roller conveyer, spaced, parallel frame members, a plurality of spaced parallel shafts supported on and extending between said frame members, pairs of bars severally supported on said shafts, said bars extending above and below said shafts, a roller revolubly supported on each pair of said bars above and to one side of the shaft supporting the same and a spring for restraining pivotal movement of each bar connected at one end to the bar below its supporting shaft and joined at the other end to the supporting shaft for another of said bars.

7. In a roller conveyer, spaced, parallel frame members, a plurality of spaced, parallel and substantially horizontal shafts supported on and extending between said frame members, pairs of bars pivotally supported on said shafts respectively for oscillating movement about the axes of said shafts, said bars projecting above and below their supporting shafts, `a roller revolubly supported on each pair of said bars above and to one side of the shaft supporting the same, a rod connecting the bars of each pair together below their supportingr shafts respectively and springs for restraining oscillating movement of said bars and rollers severally connected at one end to one of said rods and at the other end to the shaft for supporting another bar.

8. A resiliently mounted roller conveyer comprising a conveyer frame, a plurality of lever arms pivotally connected to each side rail of the conveyer frame, the lever arms on one side rail being in transverse alignment with the lever arms on the other side rail, a roller carried by each pair of transversely aligned lever arms, and tension means interconnecting each pair of lever arms and said frame.

9. A resiliently mounted roller conveyer com prising a conveyer frame, a plurality of lever arms pivotally connected to each side rail of the conveyer frame, the lever arms on one side rail being in transverse alignment with the lever arms on the other side rail, a roller carried by each pair of transversely aligned lever arms, a tension element connected to each arm `and the conveyer frame, and means limiting the pivotal movement of each arm due to the force exerted thereon by its tension element.

10. A resliently mounted roller conveyer comprising a conveyer frame, a plurality of longitudi-l nally spaced and transversely disposed rods extending between the side rails of said conveyer frame, a pair of transversely spaced lever arms carried by each rod, a roller mounted between the upper end portions of each pair of lever arms, a transversely disposed member interconnecting each pair of arms, and tension means connected between said member and the conveyer frame.

11. A resiliently mounted roller conveyer comprising a conveyer frame, a plurality of longitudinally spaced and transversely disposed rods extending between the side rails of said conveyer frame, a pair of transversely spaced lever arms carried by each rod, a roller mounted between the upper ends of each pair of lever arms, and tension means interconnecting the lower end of each arm and the conveyer frame.

12. In a roller conveyer, -a frame, a roller support, means pivotally connecting said support to said frame and eonning said support to oscillating movement about a substantially horizontal axis relative to the frame, a load supporting roll er revolubly mounted on said support and having its axis of rotation offset longitudinally of the frame from the pivotal axis of said support and resilient means connected to said frame and support and arranged to restrain pivotal movement of said support relative to the frame.

13. In a roller conveyer, a frame, a roller support, means pivotally connecting said support to said frame and confining said support to oscillating movement about a substantially horizontal axis relative to the frame, a load supporting roller revolubly mounted on said support and having its axis of rotation offset longitudinally of the frame from the pivotal axis of said support, means limiting pivotal movement of said support in one direction and resilient means restraining pivotal movement of said support in the opposite direction.

SMITH EGGLESTON. 

